Disc operating systems
- 400K/S (SD Microsystems)
- AMSDOS (Amstrad)
- BASDOS
- BonnyDOS
- MagicDOS (Logon System)
- MS800 (Microstyle)
- ParaDOS (Quantum Computing)
- RODOS (Romantic Robot)
- ROMDOS and RAMDOS (KDS/Siren Software)
- S-DOS (STS)
- SymDOS (Flynn)
- VDOS (Vortex Computersysteme)
- X-DDOS
Graphical user interfaces / Shells
- CEUS Desktop 2.0 (Prodatron)
- Desk-Royal (Crusader Software)
- Desktop (DW Software)
- DES (Desktop Environment System) (Campursoft)
- GENO (GHE)
- Max (Advanced Memory Systems)
- Mouse Operating System (M.O.S.) (Star-Division) (1987)
- SI-BOF (Bad Error) (1992)
- Stream2 (Advanced Software Project)